How large can a 1964 chevy 283 block be bored? I now the walls are pretty thick . Found one that looks like its already got .060 pistons Guy has the heads and every part of the motor decent price. block cast #3849852 figured id quickly ask here instead of looking it up
Each block needs to be examined individually to determine how large it can be bored to. Since casting methods sometimes produced shift, some blocks can't be bored as far as others. I've heard of some blocks used for drag racing got bored to .120", but they were perfect castings, and those blocks weren't used for daily street driving. Often the water jackets were poured to strengthen their lower ends also. Most 283 blocks can be bored .060" without an issue, but I'd still make sure there's no casting shift before going over .040" over bore. When I had a 283 built for my '55 Chev back in 1970 the machinist looked at the raised bosses around the soft plugs and pointed out how perfectly centered the soft plugs were in those raised bosses. He said, "This block would be perfect for a generous over bore if you wanted to go big." I didn't, but it was nice to know it had multiple larger bores if I wanted to go there.
I think a .125" overbore to 301 or 302 on early 283's was pretty common practice on race cars. Street, not so sure.
You never can say for sure, since it is already plus .060 and with piston overbore options not being what they once were it boils down to luck, really, the only way to know is by having the block sonic tested to see the consistency of the cylinder wall thickness. Now if it was an early Chevy II block the chances are better, then a .125 overbore has a better outcome as they were a popular block to use when building a 301 (.125 over).
Allegedly, the '58-'62 blocks were the best candidate for a .125 overbore. Of course, decades of corrosion now come into play. I do know that if you want to add cubes to your 283 with a crankshaft from a small journal 327, the '64-'67 blocks have sufficient clearance for the counterweights.
If its all in good shape (heads/guides) and has the old numbers that some people crave, then it may be worth buying just for all the related parts. Then if the block can stand more boring, you are in very good shape. The block may still be usable with a hone and some new rings for a daily driver or occasional driver. The only way to know for sure about the bore is to buy one of those inexpensive thickness testers off Amazon. TEMU has one for $60 and Amazon probably has some as well.
If it’s 60 over and needs boring, better off sleeving it at that point. My experience with 60 over blocks is alot of cooling issues due to the thinner walls. Going bigger just makes the issue worse for street use. My 33 pickup currently has a 60 over block and even with no hood it can’t sit in traffic long. Didn’t use to be as bad when the block was 30 over prior to its refresh.
right on ...... this one is a 1964 date. I know late late 70s and 80s blocks were light weight , thinner casting. 060 bored might end up with cracked cylinder it so thin I'll have to go look at it with some calipers... I can see in the picture looks like top of piston stamped 060. Might have ok bore and do a hone
As others have said, the block needs to be checked, really before going more than the 0.060" that you already have. You can go up to 0.125" (327/350 bore) if it's good, that makes it a 301/302 with stock stroke.
Are you asking how big an overbore the 283 can go, because it looks like it needs to go more than .060, or just questioning the current bore at plus .060 ?
You could always knurl the pistons if its not borable........(is that a word?). Not the best solution but better than scrapping a 283.
Like 1971BB said plus you can look at the cam hole in the block if it is nice and centered in that flat boss there is little core shift. I've seen some 350 blocks that have passed through my hands that were so off center I would not even use the block. And sonic testing is your best bet if you are that concerned. Pat
Core shift plays a big part in determining how to move forward on a rebuild, something most younger guys have never even heard about.
Hello, This question always is a hot topic. Everyone has their own SBC motor story. Ours was simple. We wanted to put a 283 SBC motor in a Model A we had just resurrected and had running. It was to be a simple process, pull out running motor, add motor mounts, trans, Chevy rear end and we were ready to finalize a would be fast coupe. We had several ways to go and each one was ok with us. The 283 was going to be enough for our first build and install. The 283 could be bored 1/8th over to 301. That was the safe limit for hot rod sedans and street/drag racers in our area of So Cal. There were plenty of fast cars, but Tom McEwen was always talking about “that is the way it came from the factory…” mode. (closed hood, only the sound was heard) Ha! After he won the late evening Cherry Avenue races. His 265, 283 and other mods were famous for their horsepower. Rarely did one see a 352 c.i. motor for the supercharged version at the drags. If it was 352, 1/8th over and ½ inch stroke, then it was usually multiple carburetors on top. Along with the other necessary cam/lifters/pistons, rods, crank mods, etc. From Reath Automotive: “Boring the 283 Chevy to its safe maximum results in a displacement of 301 cubic inches. From there on, the only way for additional size increases is through stroking. Conventional stroking methods run out for the 283 Chevy at 352 cubic inches. The figure is obtained with a 4 inch bore and ½ inch stroke increase over the stock 3 inch figure.” (.125 or 1/8TH over, BORE + ½ inch STROKE) Joe Reath convinced us to go to a 283 SBC for our first motor for our 40 Willys Coupe. Add in several “speed” items, pistons, polished ports/heads, cam/lifters, multiple carbs and that would be a top street level motor. Plus, it would be fast for the Gas Coupe/Sedan Classes, too. But, if we decided to stay in the gas coupe classes, a bored and stroked 352 c.i. sbc motor with multiple carbs or injection would be a top runner. Later on, we decided to go to a safe and sane 292 c.i. SBC blower spec motor. The Reath shop bored our 283 SBC motor to a 292 c.i. configuration. They said that this was a safe size for adding a supercharger. We already had the new 671 Isky-Gilmer belt drive with an Edlebrock manifold. Jnaki So, the shop put in a modified Reath crankshaft as the complete safe mode, as part of our go fast build. They modified our new 671 and were the major suppliers of all of our "blower spec" parts. Aluminum pistons, rods, modified the heads and said the completed 292 c.i. motor was assembled, it would be the safest limit for a supercharged motor. The end result became a fast E.T. that was 12.60 seconds. The national record was 12.40. So, we were close and looking forward to the next level. YRMV
And then there's this. HTTPs://www.jalopyjournal.com/forum/threads/467-cubic-inches-from-a-283.1257938/
If you knurl it used to be done a lot with mixed reviews. But I bought a old hastings machine that came with the original manual. It said only knurl the non thrust side after looking at old pistons that had been knurled the thrust side was pretty much gone while the non thrust side was good.
So those saying “have it checked” I agree, but what is a safe cylinder wall thickness when done so. Who determines what can be done, you or the shop? I assume they hand you something showing where it was tested, showing thinnest in each measurement? How does a guy know if he can use it, as in this case, to go from .060 to .080, etc? Edit: also, @JD Miller what did you end up doing?
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